听力参考文本（文本与音频不全一致，敬请谅解）：Doesn't matter to Donald Trump what his fellow Republicans say.Or what Wall Street and America's closest allies say.The president wants tariffs on imported steel and aluminum, and this week he got them, along with some last-minute carve outs for those national security threats known as Canada and Mexico.Where to start? Maybe with the improvisational policy-making, as White House staffers scrambled to put details behind the president's tariff tweets. Business and foreign capitals asked questions no one seemed able to answer. Automakers begged not to be rendered uncompetitive. Iconic exports like Harley-Davidson Motorcycles, Kentucky bourbon, and Levi's jeans became quick targets for retaliation by the European Union.And just for good measure, remnants of the Trans-Pacific Partnership coalition revived and quickly signed a slimmed down trade deal – without that pesky American president who seems to think he's Dwight Eisenhower and it's the 1950s.

Like too much else with Trump, this would be comic if it wasn't so tragic.Will costs for steel and aluminum go higher for Detroit's automakers? They already are. Will foreign governments respond with tariffs of their own? Count on it. Could a global trade tit-for-tat undercut the economic growth accelerating in the wake of tax reform? Of course it could.Why do you think Congressional Republicans are apoplectic? It's not because their high-minded principle philosophically opposes tariffs. It's because any job losses or economic slowdown pegged to Trump's tariff tirade could be blamed on Republicans in the mid-term elections.That's a whole lot of not good if you're one of them.Look, there is a case to be made for getting tough with steel dumpers from China, Russia, and Brazil. Target them. But Canada? No, this is vintage Trump negotiating: stake out a maximum position, exert leverage, and don't worry much about the collateral damage.It's also an exercise in selective facts. What a surprise.Here's what the president said when he signed the order:“Our factories were left to rot and to rust all over the place. Thriving communities turned into ghost towns. The workers who poured their souls into building this great nation were betrayed. But that betrayal is now over,” he said.Really? All because of the price of steel and aluminum produced in foreign mills? Over-simplification doesn't begin to describe it.Sectors of American industry got walloped for decades for a whole lot of different reasons, and trade rules are only one of them. Cheap foreign steel prices didn't cause General Motors to lose money building mediocre cars. Credit for that goes to bad decision-making and lazy management, and pricey labor costs didn't help.The politics of all this are suspect, too. Trump won the Electoral College with big assists from voters in the industrial heartland, especially Michigan.An escalating trade war that embroils more parts of the manufacturing economy, or spreads to the Midwest's rich agricultural sectors, could undercut economic growth and further slow already plateauing auto sales. That's hardly the makings of a robust Trump re-election campaign around here come 2020.Daniel Howes is a columnist at The Detroit News. Views expressed in his essays are his own and do not necessarily reflect those of Michigan Radio, its management or the station licensee, The University of Michigan.